Engineers in Colorado are tapping beer for energy storage

What's on tap? The makings of advanced batteries and a better way to deal with brewery wastewater.

Engineers at University of Colorado Boulder have come up with a process to make lithium-ion battery electrodes from the sugar-rich wastewater created in the beer-making process. The bio-manufacturing process is not only a sustainable source for battery materials and fuel cells, but it's also an inexpensive way to deal with the large amount of wastewater breweries produce.

“Breweries use about seven barrels of water for every barrel of beer produced,” said Tyler Huggins, a graduate student in CU Boulder’s Department of Civil, Environmental and Architectural Engineering and lead author of the new study. “And they can’t just dump it into the sewer because it requires extra filtration.”

The use of biomass in battery and fuel cell technologies isn't new, but the researchers found that the beer wastewater was especially suited to the task. They found that they could easily cultivate a fast-growing fungus, Neurospora crassa, which then becomes the carbon-based electrode, in the wastewater. The partnership between the researchers and breweries is mutually beneficial: the scientists need a sugar-rich material for cultivating the fungus and the breweries have a lot of wastewater that needs to be treated.

The university said, "By cultivating their feedstock in wastewater, the researchers were able to better dictate the fungus’s chemical and physical processes from the start. They thereby created one of the most efficient naturally-derived lithium-ion battery electrodes known to date while cleaning the wastewater in the process."

The process could easily be scaled up because everything needed to produce the energy storage material already exists. The engineers are teaming up with Avery Brewing in Boulder to work on a large pilot program. Watch the video below to hear more about the process.